STEP 1. Launch iTunes to set the Preferences

Choose Preferences. Then click Advanced and check on the box beside
"Share iTunes Library XML with other applications".

STEP 2. Quit your iTunes.

STEP 3. Now run your M4V Converter and take a try.

If still you can't find any M4V video in converter,
please drag the M4V files to the M4V converter directly from your file folder.

About the iTunes Library.xml file

This file contains some (but not all) of the same information stored in the iTunes Library file.
The purpose of the iTunes Library.xml file is to make your music and playlists available to other applications
on your computer.